secondary cells with lithium anodes and immobilized fused_salt

The energies and Enthalpies of activation indicate that chemi-
cal reactions but not physical processes are rate-controlling. The
probable chemi ca 1 re. ac tions oc c urr.ing during hydrocracking are
cracking, .isomer.ization,. hydrogenation, polymerization, condensation,
and dehydrogenation, all taking place on the catalyst surface. Under
the experimental conditions employed polymerization, condensation,
and dehydrogenation are very muc.h suppressed and may be eliminated.
It has been established by Weirz and Prater (1957) and Keulemans
I and Voge (19.59) that reactions occurring on acidic sites of the
1 , dual-functional catalyst, like the one used in this investigation,
?
are rate-determining wh.ich eliminates the possibility of hydrogena-
tion reactions to be rate-.limi ting. Hence. cracking reactions
involving the breakage of chemical bonds and the isomerization
reactions, wl!ere in skeletal rearrangement of carbonium ions takes
I place, must be rate-limiting. ' It is known that in catalytic hydro-
I cracking, cracking precedes isomerization and only the isomeriza-
! tion of the cracked fragments occurs without any change of the
I
33.
1960). An excess of branched isomers than can be predicted by
thermodynamic equilibrium are also formed; the latter can only
happen if the isomerization of the cracked fragments can occur
very rapidly and leave the catalyst surface without appreciable
readsorption. Tharefore., the isomerization is believed to be very
rapid and cannot ba rate-controlling. HPnce, the cracking reactions,
involving the breakage of chemical bonds on the catalyst
surf ace, are ra te-de term ining .
- Ac k no w led Pmen t
) uncracked material (Flinn, et ale, 1960, and Archibald, et al.,
,I
)
The research work reported in this paper was sponsored by the
U. S. Office of Coal Research and the University of Utah.
,